Adaptive track assembly

CROSS REFERENCE TO RELATED APPLICATIONS

0001This application is a continuation-in-part of U.S. application Ser. No. 16/352,774, filed Mar. 13, 2019, which claims priority to and the benefit of U.S. Provisional Application No. 62/642,698, filed Mar. 14, 2018. Each of these two applications is incorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION

0002This disclosure relates to multi-terrain transport apparatuses. More particularly, but not by way of limitation, this disclosure relates to adaptive track assemblies for use in motorized wheelchairs or other personal transport apparatuses.

0003Conventional wheelchairs face difficulties when traversing uneven terrain or negotiating obstructions in the terrain. One difficulty is being unable to proceed when a wheel becomes stuck in a depression, such that when the user attempts to free himself/herself, the chair may be upset. A similar problem, with the same consequences, occurs when attempting to traverse obstructions, such as rocks, logs, or curbs, in the path of the wheelchair.

0004Other personal transport apparatuses may face similar challenges when traversing uneven terrain.

BRIEF SUMMARY OF THE INVENTION

0005The present inventors recognize the need for a track unit for a multi-terrain transport apparatus, such as a motorized wheelchair, that allows users to adjust a surface area of a continuous track depending on the terrain encountered by the transport apparatus.

0006A multi-terrain transport apparatus can comprise at least a track unit. The track unit can include a suspension mounting assembly, an adaptive track assembly, and a continuous track surrounding portions of the suspension mounting and adaptive track assemblies. The adaptive track assembly can include a track side plate, a front idler wheel coupled to a first portion of the track side plate, a second idler wheel coupled to a second portion of the track side plate, a track arm, a track arm idler wheel coupled to the track arm, and an actuator. The actuator can be coupled on its first end portion to the track side plate, coupled on its second end portion to the track arm, and configured to control positioning of the track arm idler wheel in response to changes in terrain. Changes in the positioning of the track arm idler wheel can increase and decrease contact of the continuous track with the terrain.

0007A multi-terrain transport apparatus can comprise at least one track unit having an adaptive track assembly and a continuous track surrounding portions of the adaptive track assembly. The adaptive track assembly includes an arm, an adaptive wheel coupled to the arm, and an actuator coupled to the arm, and the actuator is configured to control positioning of the adaptive wheel to modify an amount of surface area of the continuous track in contact with the terrain. The actuator can be configured to position the adaptive wheel towards the terrain to decrease the amount of surface area of the continuous track in contact with the terrain. The actuator can be configured to position the adaptive wheel away from the terrain to increase the amount of surface area of the continuous track in contact with the terrain. The track unit can comprise a front wheel and the continuous track surrounds portions of the front wheel and the front wheel is configured to have a variable position. The track unit further can comprise a track tensioner configured to adjust the track tension on the continuous track. The apparatus can include a balance control apparatus configured to deploy when the amount of surface area of the continuous track in contact with the terrain is decreased. The apparatus can include a stabilizing bar and a second track unit, the stabilizing bar connecting the track units.

0008These and other examples and features of the present apparatuses and associated assemblies will be set forth, at least in part, in the following Detailed Description. This Brief Summary is intended to provide non-limiting examples of the present subject matter—it is not intended to provide an exclusive or exhaustive explanation. The Detailed Description below is included to provide further information about the present apparatuses and assemblies.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, like numerals can be used to describe similar features and components throughout the several views. The drawings illustrate generally, by way of example, but not by way of limitation, various embodiments discussed in this disclosure.

<figref idref="DRAWINGS">FIG. <b>1</b></figref> illustrates a side view of a motorized wheelchair including a track unit, as constructed in accordance with at least one embodiment of the present disclosure.

<figref idref="DRAWINGS">FIG. <b>2</b></figref> illustrates a back view of a motorized wheelchair including a track unit, as constructed in accordance with at least one embodiment of the present disclosure, with the track removed on the left side.

<figref idref="DRAWINGS">FIG. <b>3</b></figref> illustrates a side view of a track unit including a suspension mounting assembly and track unit assembly, as constructed in accordance with at least one embodiment of the present disclosure.

<figref idref="DRAWINGS">FIG. <b>4</b></figref> illustrates a side view of a track unit including a suspension mounting assembly and an adaptive track assembly, as constructed in accordance with at least one embodiment of the present disclosure, with the track removed.

<figref idref="DRAWINGS">FIG. <b>5</b></figref> illustrates a perspective exploded view of a track unit including a suspension mounting assembly and an adaptive track assembly, as constructed in accordance with at least one embodiment of the present disclosure.

<figref idref="DRAWINGS">FIG. <b>6</b></figref> illustrates a side view of a track unit including a suspension mounting assembly and an adaptive track assembly, as constructed in accordance with at least one embodiment of the present disclosure.

<figref idref="DRAWINGS">FIG. <b>7</b></figref> illustrates a side view of a balance control apparatus, as constructed in accordance with at least one embodiment of the present disclosure.

<figref idref="DRAWINGS">FIG. <b>8</b></figref> illustrates a perspective exploded view of a track unit including an adaptive track assembly and a balance control apparatus, as constructed in accordance with at least one embodiment of the present disclosure.

<figref idref="DRAWINGS">FIG. <b>9</b></figref> illustrates a side view of an adaptive track assembly in a continuous track minimum surface area condition as constructed in accordance with at least one embodiment of the present disclosure. In this view, the track unit in the foreground is removed.

<figref idref="DRAWINGS">FIG. <b>10</b></figref> illustrates a side view of an adaptive track assembly in a continuous track maximum surface area condition, as constructed in accordance with at least one embodiment of the present disclosure. In this view, the track unit in the foreground is removed.

<figref idref="DRAWINGS">FIG. <b>11</b></figref> illustrates an end view of the main frame and related stability links as constructed in accordance with at least one embodiment of the present disclosure. In this view, the track units and balance control apparatus are removed.

<figref idref="DRAWINGS">FIGS. <b>12</b>A and <b>12</b>B</figref> illustrate perspective views of tracks as constructed in accordance with certain embodiments of the present disclosure.

0022The drawings are not necessarily to scale. Certain features and components may be shown exaggerated in scale or in schematic form, and some details may not be shown in the interest of clarity and conciseness.

DETAILED DESCRIPTION

0023With reference to <figref idref="DRAWINGS">FIGS. <b>1</b> through <b>11</b></figref>, a new adaptive track assembly for use in a motorized wheelchair or other personal transport apparatus or vehicle is disclosed.

0024<figref idref="DRAWINGS">FIG. <b>1</b></figref> illustrates a side view of a motorized wheelchair including a track unit, as constructed in accordance with at least one embodiment of the present disclosure. In greater detail, <figref idref="DRAWINGS">FIG. <b>1</b></figref> illustrates that a seating system <b>10</b> can comprise a back support <b>14</b>, a backrest portion <b>15</b>, and one or more arm rests <b>16</b>. The seating system can also comprise a seat cushion portion <b>18</b> and a foot rest unit <b>19</b>. The back support <b>14</b> can be configured to be capable of reclining to adjust the center of gravity of the combination of the user and the apparatus. The backrest portion <b>15</b> and the seat cushion portion <b>18</b> are configured to be comfortable for the user and can be made of a suitable cushioning material, such as foam that is wrapped in fabric, or any equivalent seating and support material. Optionally, foam or equivalent padding can be positioned on either lateral side of the seating system <b>10</b>. Optionally the one or more arm rests <b>16</b>, can include a cushioned or padded material. The foot rest unit <b>19</b> can be solid mounted, or it can be adjustable manually or automatically to allow the user to tilt the foot rest forward to allow for adjusting to terrain. The foot rest unit <b>19</b> can include a foot rest platform <b>20</b> that can be adjusted manually or automatically.

0025Hand controls <b>17</b> can include an interface device for controlling the mechanical functions of the motorized wheelchair, such as a joystick, screen, and control buttons or switches, and may be attached to the arm rests <b>16</b> to operate functions such as forward and rearward motion, steering, speed, adaptive track adjustment, and balance control apparatus deployment. The hand controls <b>17</b> can also control seating system <b>10</b> functions, such as tilt, recline, elevation, foot rest adjustments, and horizontal sliding of seating system <b>10</b> forward and rearward to adjust the center of gravity or the position of the seating system <b>10</b>. More generally, any control system adapted to and suitable for the physical capabilities of the user is included in this disclosure. That is, the control systems useful for integration with embodiments of the disclosure are not limited to hand controls.

0026Referring still to <figref idref="DRAWINGS">FIG. <b>1</b></figref>, the seating system <b>10</b> can further include a seat base support portion <b>21</b> that supports the seat cushion <b>18</b> and user, a scissor lift system <b>22</b> that allows for seat system to tilt and elevate, and a seat system mounting bracket <b>23</b> that can be solid mounted or can include suspension.

0027The seating system <b>10</b> can be pivotably mounted at the seat base support portion <b>21</b> with respect to the track units <b>12</b>, <b>13</b> and be capable of tilting forward and rearward so the user can adjust to going up inclines or down declines (only track unit <b>13</b> is pictured in the view illustrated by <figref idref="DRAWINGS">FIG. <b>1</b></figref>). The seating system <b>10</b> can also adjust forward and rearward parallel to track units <b>12</b>, <b>13</b>. The seating system <b>10</b> and its functions can be operated by electric, pneumatic, and/or hydraulic actuator units. The actuator units described herein can include electric motors, gear sets (e.g., gear boxes), pistons, rods, rotational linkages, and/or the like. Some actuator units may be linear actuators that bi-directionally move along an axis. The linear actuators may include telescoping elements that telescope when extending as retracting, but the linear actuators described herein are not limited to telescoping operations. Other actuator units may only include a motor and associated gear set to affect movement of another component. The seating system <b>10</b> can be configured to automatically adjust to different terrain and environments without user input.

0028<figref idref="DRAWINGS">FIG. <b>2</b></figref> illustrates a back view of a motorized wheelchair including track units <b>12</b>, <b>13</b>, as constructed in accordance with at least one embodiment of the present disclosure, with the track removed on the left side. The seating system <b>10</b> can be coupled to the main frame <b>11</b> and at least one drive system <b>24</b>, which may include a drive motor. Each drive system <b>24</b> can be configured to drive one track unit <b>12</b>, <b>13</b> independent of the other drive system <b>24</b>. For clarity, the operation of the drive system and track units will be described with reference to a single combination of a drive system and track unit. But all descriptions of the operation of this single combination of a drive system and track unit are applicable to other combinations of a drive system and track unit referenced or depicted in this disclosure.

0029Drive system <b>24</b> can include a gear box and a drive shaft, and the drive shaft may be coupled to drive sprocket <b>33</b> that drives the continuous track <b>29</b>. The continuous track <b>29</b> may contain raised features (such as ridges, knobs, and/or knurls) to help prevent the continuous track <b>29</b> from losing traction when propelling the motorized wheelchair forward or rearward. The main frame <b>11</b> may also contain a power source <b>25</b> providing power to the motorized wheelchair, including to the drive system <b>24</b> and the seating system <b>10</b>. The power source <b>25</b> can include at least one battery. Alternately or additionally, a combustion engine can be used in the power source <b>25</b> for the motorized wheelchair. The main frame <b>11</b> may also contain additional electrical components for operation of the motorized wheelchair, such as motor controllers and a wire harness.

0030Referring now to <figref idref="DRAWINGS">FIG. <b>2</b></figref>, <figref idref="DRAWINGS">FIG. <b>3</b></figref>, and <figref idref="DRAWINGS">FIG. <b>5</b></figref>, the track unit <b>12</b>, <b>13</b> may have a generally triangular configuration and can be coupled to the main frame <b>11</b> via a suspension mounting bracket <b>27</b>. A suspension member <b>32</b> (for example, a torsional spring damper system, a coil over shocks, or rubber torsion bars) can be coupled to the mounting bracket <b>27</b>. Suspension arms <b>36</b> can pivotably connect the suspension member <b>32</b> to track channel side plates <b>37</b>. The track channel side plates <b>37</b> may be connected to each other via connection plates <b>34</b> and idler wheel shafts <b>28</b>. The assembled track channel side plates <b>37</b> can make up one track channel and through the pivoting connections created by the suspension arms <b>36</b> and suspension members <b>32</b>. The track channel can move laterally and vertically with respect to the main frame <b>11</b> to add suspension and damping to the motorized wheelchair. The suspension and damping systems disclosed herein are examples of such systems, and other suspension and damping systems can be used in conjunction with the other systems disclosed herein with the goal of providing adjustable surface area of a continuous track and/or an adaptive track assembly for a motorized personal vehicle such as a wheelchair.

0031Referring now to <figref idref="DRAWINGS">FIG. <b>2</b></figref>, <figref idref="DRAWINGS">FIG. <b>3</b></figref>, and <figref idref="DRAWINGS">FIG. <b>5</b></figref>, idler wheels <b>35</b> are located at forward and rearward positions in the track units <b>12</b>, <b>13</b>. Idler wheels <b>35</b> can freely rotate (that is, they are not driven by a drive unit, but embodiments in which these wheels are driven by a drive unit are included in this disclosure) and allow the continuous track <b>29</b> to have a generally triangular shape when used in conjunction with drive sprocket <b>33</b>. Idler wheels <b>35</b> can be connected to respective idler wheel shafts <b>28</b>. Optionally, multiple idler wheels <b>35</b> may be mounted to the same idler wheel shaft <b>28</b>. Idler wheels <b>35</b> are configured to allow for an approach angle of the track units <b>12</b>, <b>13</b>. That is, the lower forward and lower rearward portions of the continuous track <b>29</b> are not necessarily in contact with the terrain due to the positioning of the idler wheels <b>35</b>, allowing the continuous track <b>29</b> to have an approach angle with respect to the terrain and minor variations in the terrain. In some embodiments, the approach angle is adjustable by varying the position of the idler wheels <b>35</b> within the generally triangular shape of the continuous track <b>29</b>.

0032At least one dynamic track tensioner <b>30</b> with tensioner idler wheel <b>31</b> can be included in the track units <b>12</b>, <b>13</b>, such as by being mounted to connection plate <b>34</b>. The combination of one dynamic track tensioner <b>30</b> with tensioner idler wheel <b>31</b> allows for adjustable track tension on the continuous track <b>29</b>. Alternatively, static track tensioners can be used in place of the dynamic track tensioner and can be placed at various locations within the track units <b>12</b>, <b>13</b>. At least one stabilization bar <b>26</b> can be used to connect the track units <b>12</b>, <b>13</b> to each other and allows for the user to be able to manually adjust pitch and camber of track units. In another configuration, stabilization bars can be pivotably connected to the main frame <b>11</b> and to each track unit <b>12</b>, <b>13</b>. In another alternative, stabilization can also be achieved without stabilization bars by increasing the strength of the suspension members <b>32</b> and the suspension arms <b>36</b>.

0033Another configuration that can be implemented includes direct mounting of the track channel side plates <b>37</b> to the main frame <b>11</b>. In this configuration, the mounting bracket <b>27</b>, the suspension member <b>32</b>, and the suspension arms <b>36</b> would not be present in the track units <b>12</b>, <b>13</b>. In such a configuration, the suspension elements may be present in the main frame <b>11</b> or other locations in the motorized personal vehicle to provide any desired suspension and/or dampening characteristics and functions.

0034Referring now to <figref idref="DRAWINGS">FIG. <b>4</b></figref> and <figref idref="DRAWINGS">FIG. <b>5</b></figref>, each track unit <b>12</b>, <b>13</b> can include an adaptive track assembly <b>40</b>, which can be pivotably connected to the track channel side plates <b>37</b> via the track arms <b>39</b>. The adaptive idler wheels <b>42</b> are connected to the track arms <b>39</b>, which are configured to contact the continuous track <b>29</b> at locations along the continuous track <b>29</b> that are between the idler wheels <b>35</b>. A shaft can connect the adaptive idler wheels <b>42</b> to the track arms <b>39</b>. End stops <b>38</b> can be connected to the channel side plates <b>37</b> and define the range of motion of the pivoting of the track arms <b>39</b>. In certain configurations, only one end stop <b>38</b> may be present, but generally two end stops <b>38</b> are useful for defining the range of motion of each track arm <b>39</b>. The end stops <b>38</b> can be made of any suitably strong and resilient material, including, but not limited to, rubber and sheet metal. Each track arm <b>39</b> can rotate between the nearby end stops <b>38</b> and can be manually rotated or power rotated with actuator units, such as linear actuators. Linear actuator units can comprise an actuator bracket <b>45</b> which is pivotably connected the track channel side plates <b>37</b> through an actuator pin <b>41</b>. The actuator bracket <b>45</b> can be connected to the actuator housing <b>46</b>, and the actuator housing <b>46</b> can drive the actuator rod <b>44</b> to extend or contract. The actuator rod <b>44</b> has actuator block <b>43</b> connected to an end of the actuator rod <b>44</b>. The actuator block <b>43</b> has a pivot portion that is connected to the track arm <b>39</b>, such as at a middle rotational shaft on the track arm <b>39</b>.

0035The actuator units cooperate with the track arms <b>39</b> and the end stops <b>38</b> to move the adaptive idler wheels <b>42</b> to change the surface area of the continuous track <b>29</b> that is in contact with the terrain. When the actuator rod <b>44</b> is in an extended position, the track arm <b>39</b> is in a position against the outer end stop <b>38</b> (that is, the end stop nearer to the idler wheels <b>35</b>). With the adaptive idler wheels <b>42</b> in this extended position, the most track surface area possible of the continuous track <b>29</b> is in contact with the terrain, thereby allowing the motorized wheelchair to travel over rough terrain. When the actuator rod <b>44</b> is in a contracted position, the track arm <b>39</b> is in a position against the inner end stop <b>38</b> (that is, the end stop farther from the idler wheels <b>35</b>). With the adaptive idler wheels <b>42</b> in this contracted position, the least track surface area possible of the continuous track <b>29</b> is in contact with terrain. The contracted position of the adaptive idler wheels <b>42</b> decreases the surface area of the continuous track <b>29</b>, such as by more or less than 85%, which allows for easier turning on carpet or pavement.

0036The actuator units control the motion of the track arms <b>39</b> as the track arms <b>39</b> pivot from the outer end stops <b>38</b> to the inner end stops <b>38</b>. In some embodiments, the actuator units themselves are equipped with features that control the range of motion of the track arms <b>39</b> and one or both of the end stops <b>38</b> are not necessary. The track unit <b>12</b>, <b>13</b> can include at least one independently operated actuator unit. Another configuration for the adaptive track assembly is a scissor-lift style configuration composed of linkages and actuators that changes the position of the adaptive idler wheels to cause changes to the surface area of the continuous track. In some embodiments, adaptive track assemblies can be configured to automatically adjust for different terrain and environment without user input by sensing and responding to the terrain and environment.

0037The embodiments disclosed in <figref idref="DRAWINGS">FIGS. <b>1</b> through <b>5</b></figref> relate to an adaptive track assembly that deploys two adaptive wheels per track unit to modify the terrain-contacting surface area of the continuous track and the embodiments exemplify a way of achieving that result. Other embodiments that deploy two adaptive wheels per track unit to modify the terrain-contacting surface area of the continuous track are contemplated to be within the scope of this disclosure and the disclosure is not limited to the specific arrangement of parts and features disclosed in <figref idref="DRAWINGS">FIGS. <b>1</b> through <b>5</b></figref>.

0038Referring now to <figref idref="DRAWINGS">FIG. <b>6</b></figref> and <figref idref="DRAWINGS">FIG. <b>8</b></figref>, track unit <b>111</b> may have a generally triangular configuration and can be coupled to a main frame of a personal vehicle such as a motorized wheelchair. A suspension member <b>118</b> (for example torsional spring damper system, coil over shocks, or rubber torsion bars) can be coupled to a suspension mounting bracket that connects to the main frame of the motorized wheelchair. Suspension arms <b>119</b> can pivotably connect the suspension member <b>118</b> to the track unit frame <b>120</b>. One or more rear idler wheels <b>121</b> are connected to the track unit frame <b>120</b>. The rear idler wheels <b>121</b> can freely rotate about idler wheel shafts <b>123</b> (that is, they are not driven by a drive unit, but embodiments in which these wheels are driven by a drive unit are included in this disclosure). The combination of the rear idler wheels <b>121</b>, the drive sprocket <b>125</b>, and the forward idler <b>128</b> allows the continuous track <b>122</b> to take the look of a generally triangular shape. When more than one rear idler wheel <b>121</b> is present, these wheels are configured to allow for an approach angle for the track unit <b>111</b> by placing the rearward idler wheel higher than the forward idler wheel. In some embodiments, the approach angle is adjustable by varying the position of the rear idler wheels <b>121</b> within the generally triangular shape of the continuous track <b>122</b>. The track unit frame <b>120</b> can move laterally and vertically to add suspension and damping to the motorized wheelchair.

0039The track unit <b>111</b> includes, or is operatively connected to, a drive system <b>124</b>, which may include a drive motor. The drive system <b>124</b> can be configured to drive one track unit <b>111</b> independent of the other drive system connected to the other track unit on the other side of the motorized wheelchair. The drive system <b>124</b> can include a gear box and a drive shaft, which may be coupled to the drive sprocket <b>125</b> that drives the continuous track <b>122</b>. The continuous track <b>122</b> may contain raised features (such as ridges, knobs, and/or knurls) to help prevent the continuous track <b>122</b> from losing traction when propelling the motorized wheelchair forward or rearward.

0040Referring now to <figref idref="DRAWINGS">FIGS. <b>12</b>A and <b>12</b>B</figref>, the continuous track <b>122</b> may have a center continuous depth band <b>146</b> on the part of the continuous track <b>122</b> that engages with the terrain, allowing for smooth operation by decreasing the vibrations transferred through the continuous track <b>122</b> and into middle idler wheel <b>127</b> when in the minimum surface area condition <b>108</b> depicted in <figref idref="DRAWINGS">FIG. <b>9</b></figref>. To increase track traction, traction grooves <b>147</b> are formed on a side of the track that is away from the continuous center depth band. Traction grooves <b>147</b> allow for traction in snow and mud applications. The positive drive grooves/lugs <b>148</b> inside of the continuous track <b>122</b> engage drive sprocket <b>125</b>. In certain embodiments, the idler wheels can be designed to have variable diameter on their outer edges while the diameter of the center of the idler wheels stays constant. A larger outer diameter on the idler wheels can force the continuous track to flex downward while leaving the center depth band at a fixed, continuous depth. This arrangement can allow for greater traction.

0041The track unit <b>111</b> includes an adaptive track assembly, which can include an adaptive track arm <b>126</b> that is configured to pivot at or near the midpoint of the adaptive track arm <b>126</b>. The adaptive track arm <b>126</b> connects with a middle idler <b>127</b> and a forward idler <b>128</b> such that the pivot point of the adaptive track arm <b>126</b> is between the middle idler <b>127</b> and the forward idler <b>128</b>. The adaptive track arm <b>126</b> is adjusted about its pivot point manually or using power with actuator units, such as linear actuators.

0042A linear actuator unit <b>129</b> is connected to the adaptive track arm <b>126</b>, which is pivotably connected to track unit frame <b>120</b>. At least one end stop <b>130</b> can be connected to the track unit frame <b>120</b> and can be made of any suitably strong and resilient material, including, but not limited to, rubber and sheet metal. The end stop <b>130</b> defines at least part of the range of motion of the adaptive track arm <b>126</b> and protects the adaptive track arm <b>126</b> from pivoting too far.

0043As the linear actuator unit <b>129</b> extends, the adaptive track arm <b>126</b> is rotated about its pivot point in a counter clockwise direction (in the view depicted in <figref idref="DRAWINGS">FIG. <b>6</b></figref>). More generally, operation of the linear actuator unit <b>129</b> extends the middle idler <b>127</b> towards the terrain. As the adaptive track arm <b>126</b> continues to rotate in a counter clockwise direction, the surface area of the continuous track <b>122</b> that is directly beneath the middle idler <b>127</b> defines the surface area that is in contact with terrain. Also, as the adaptive track arm <b>126</b> continues to rotate in a counter clockwise direction, the forward idler <b>128</b> rotates up, thereby keeping the continuous track <b>122</b> at approximately the same tension (e.g., within a designated tolerance range of 3%, 5%, 7%, 10%, or the like). This continuous track minimum surface area condition <b>108</b> is depicted in <figref idref="DRAWINGS">FIG. <b>9</b></figref>. In the continuous track minimum surface area condition <b>108</b>, the surface area of the continuous track that contacts the terrain is decreased by more or less than 95% which allows for easier turning on carpet or pavement.

0044To increase the amount of surface area that is in contact with the terrain, the linear actuator unit <b>129</b> contracts and rotates the adaptive track arm <b>126</b> clockwise (in the view depicted in <figref idref="DRAWINGS">FIG. <b>6</b></figref>) to bring the middle idler <b>127</b> away from the terrain. The clockwise rotation of the adaptive track arm <b>126</b> also rotates the forward idler <b>128</b> such that the middle idler <b>127</b> and the forward idler <b>128</b> are substantially in line with each other. This aligned arrangement puts the continuous track <b>122</b> into the continuous track maximum surface area condition <b>109</b> depicted in <figref idref="DRAWINGS">FIG. <b>10</b></figref>. Adaptive track assemblies can be configured to automatically adjust for different terrain and environment without user input.

0045The adaptive track arm <b>126</b> can include a static track tensioner <b>131</b> used to initially tension the continuous track <b>122</b> to correct the length and tension and also allow for adjustable track tension on the continuous track <b>122</b>. The static track tensioner <b>131</b> can be placed in many other locations to provide tension on the continuous track <b>122</b> and is not limited to this location. A dynamic tensioner can be used in place of the static track tensioner.

0046Referring now to <figref idref="DRAWINGS">FIG. <b>7</b></figref>, <figref idref="DRAWINGS">FIG. <b>8</b></figref>, and <figref idref="DRAWINGS">FIG. <b>11</b></figref>, the main frame <b>110</b> of the motorized wheelchair contains a caster arm linkage assembly <b>112</b> in caster arm linkage assembly compartments <b>115</b> of the main frame <b>110</b>. <figref idref="DRAWINGS">FIG. <b>11</b></figref> illustrates an end view of the main frame <b>110</b> include stability links, with track units <b>111</b> and caster arm linkage assembly <b>112</b> removed. The caster arm linkage assembly <b>112</b> includes a front caster arm <b>133</b> connected to a caster wheel assembly <b>134</b> in which the wheel of the caster wheel assembly <b>134</b> is free to rotate while in contact with the terrain. A rear caster arm <b>135</b> is connected to another caster wheel assembly <b>134</b> in which the wheel of the caster wheel assembly <b>134</b> is free to rotate while in contact to the terrain. The front caster arm <b>133</b> and rear caster arm <b>135</b> can be rotatably connected to the main frame <b>110</b> via a suitable connecting member, such as caster arm pins <b>136</b>.

0047A rotational block <b>137</b> is rotatably connected to the main frame <b>110</b> via a suitable connecting member, such as block pin <b>138</b>. The rotational block <b>137</b> is secured to the rear caster arm <b>135</b> through a caster link <b>142</b>, which includes securing members such as the caster link pins <b>141</b>. The rotational block <b>137</b> is connected to the front caster arm <b>133</b> through a shock absorbing member, such as a shock tower <b>140</b>, and is secured to the shock tower <b>140</b> via a suitable connecting member, such as shock pins <b>139</b>. The shock tower <b>140</b> allows the front caster wheel assembly <b>134</b> to adjust to different terrain, to adjust to ascending and descending hills, and more generally to maintain contact with varied terrain when the front caster wheels <b>134</b> are deployed.

0048The caster arm linkage assembly <b>112</b> is deployed through an actuator, such as the linear actuator <b>143</b>, which is connected to the main frame <b>110</b> via a suitable connecting member, such as an actuator back pin <b>144</b>. The linear actuator <b>143</b> is connected to the rotational block <b>137</b> via a suitable connecting member, such as an actuator block pin <b>145</b>. When the linear actuator <b>143</b> extends, it causes the rotation block <b>137</b> to rotate counter clockwise (in the view illustrated in <figref idref="DRAWINGS">FIG. <b>7</b></figref>). The counter clockwise movement of the rotation block <b>137</b> moves the front caster arm <b>133</b> and the rear caster arm <b>135</b> such that the caster wheel assemblies <b>134</b> connected to the front caster arm <b>133</b> and the rear caster arm <b>135</b> are retracted away from the terrain. Retracting the caster wheel assemblies <b>134</b> away from the terrain coincides with the continuous track maximum surface area condition <b>109</b> depicted in <figref idref="DRAWINGS">FIG. <b>10</b></figref>. When the linear actuator <b>143</b> retracts, it causes the rotation block <b>137</b> to rotate clockwise (in the view illustrated in <figref idref="DRAWINGS">FIG. <b>7</b></figref>). The clockwise movement of the rotation block <b>137</b> moves the front caster arm <b>133</b> and the rear caster arm <b>135</b> such that the caster wheels assemblies <b>134</b> connected to the front caster arm <b>133</b> and the rear caster arm <b>135</b> are deployed toward the terrain. Deploying the caster wheel assemblies <b>134</b> toward the terrain coincides with the continuous track minimum surface area condition <b>108</b> depicted in <figref idref="DRAWINGS">FIG. <b>9</b></figref>. In the continuous track minimum surface area condition <b>108</b>, the caster wheel assemblies <b>134</b> provide additional balance control and stability to the motorized wheelchair while not substantially increasing the terrain-contacting surface area of the motorized wheelchair.

0049The embodiments disclosed in <figref idref="DRAWINGS">FIGS. <b>6</b> through <b>10</b></figref> relate to an adaptive track assembly that deploys one adaptive wheel per track unit to modify the terrain-contacting surface area of the continuous track and the embodiments exemplify a way of achieving that result. Other embodiments that deploy one adaptive wheel per track unit to modify the terrain-contacting surface area of the continuous track are contemplated to be within the scope of this disclosure and the disclosure is not limited to the specific arrangement of parts and features disclosed in <figref idref="DRAWINGS">FIGS. <b>6</b> through <b>10</b></figref>. Also, <figref idref="DRAWINGS">FIGS. <b>7</b> through <b>10</b></figref> disclose an embodiment of a balance control apparatus in the form of a caster wheel assembly. Other embodiments of a balance control apparatus that provide additional balance control and stability to the motorized wheelchair while not substantially increasing the terrain-contacting surface area of the motorized wheelchair are contemplated to be within the scope of this disclosure and the disclosure is not limited to the specific arrangement of parts and features disclosed in <figref idref="DRAWINGS">FIGS. <b>7</b> through <b>10</b></figref>.

0050Another example of the balance control apparatus is a gyroscopic system that controls the drive system to automatically provide balance and stability (at least when in the minimum surface area condition) by continuously controlling the direction and speed at which the continuous track rotates to counteract excessive acceleration that could lead to a fall. The gyroscopic system may include one or more sensors, such as a gyroscope and/or an accelerometer, and a controller with one or more processors. The controller may generate control signals for controlling the drive system based on sensor signals generates by the one or more sensors of the gyroscopic system. Optionally, the multi-terrain transport apparatus may include both the gyroscopic system and at least one caster arm linkage assembly.

0051Referring now to <figref idref="DRAWINGS">FIG. <b>11</b></figref>, the seating system can be coupled to the main frame <b>110</b>, which includes at least one battery compartment <b>114</b> housing one or more of a battery, electrical wiring, and/or electrical components. The main frame <b>110</b> includes at least one caster arm linkage assembly compartment <b>115</b> which in turn houses the caster arm link assembly <b>112</b> as disclosed in the description above. The main frame <b>110</b> has two compartments <b>115</b> in the illustrated embodiment, but may have only one, central compartment in an alternative embodiment. The main frame <b>110</b> connects to the track units <b>111</b> (depicted in <figref idref="DRAWINGS">FIG. <b>6</b></figref>) via the suspension mounting brackets <b>116</b>. At least one stabilization bar <b>117</b> can be used to connect track units <b>111</b> to the main frame and the stabilization bar(s) <b>117</b> allows for the user to manually adjust the pitch and camber of the track units <b>111</b>. In another configuration, stabilization bars can be pivotally interconnected with the left and right track units rather than with the main frame. In yet another configuration, stabilization can be achieved without stabilization bars by increasing the strength of the track unit mounting brackets <b>116</b>, suspension members <b>118</b>, and suspension arms <b>119</b>. In yet another configuration, the track units are fixedly mounted to the main frame.

0052In one aspect of the disclosure, a multi-terrain transport apparatus comprises at least a track unit including an adaptive track assembly and a continuous track surrounding portions of the adaptive track assembly. The adaptive track assembly includes a track side plate, a front idler wheel coupled to a first portion of the track side plate, a second idler wheel coupled to a second portion of the track side plate, a track arm, a track arm idler wheel coupled to the track arm, and an actuator. The actuator is coupled on a first end portion to the track side plate, coupled on a second end portion to the track arm, and configured to control positioning of the track arm idler wheel in response to changes in terrain, thereby increasing and decreasing contact of the continuous track with the terrain.

0053In another aspect of the disclosure, the track arm is rotatably coupled to the track side plate on its first end portion, is coupled with the track arm idler wheel on its second end portion, and is coupled with the actuator along its intermediate portion.

0054In another aspect of the disclosure, the adaptive track assembly further comprises at least one end stop positioned to limit movement of the track arm.

0055In another aspect of the disclosure, the at least one end stop includes a first end stop and a second end stop, where the first end stop is positioned closer to the front idler wheel than the second end stop.

0056In another aspect of the disclosure, the track arm moves between the first and second end stops.

0057In another aspect of the disclosure, the actuator is pivotably coupled to the track side plate on its first end portion.

0058In another aspect of the disclosure, the actuator includes an actuator housing, an actuator rod, and an actuator block.

0059In another aspect of the disclosure, the actuator rod has a telescoping configuration movable between a longer length and a shorter length.

0060In another aspect of the disclosure, the actuator is powered by electric, hydraulic, or pneumatic means.

0061In another aspect of the disclosure, the adaptive track assembly includes first, and second sets of the track arm and the track arm idler wheel is coupled to the track arm, the first set is positioned closer to the front idler wheel and the second set is positioned closer to the rear idler wheel.

0062In another aspect of the disclosure, the apparatus comprises a suspension mounting assembly including a suspension side plate and at least one suspension arm coupled on a first end portion to the suspension side plate and coupled on a second end portion to the track side plate.

0063In another aspect of the disclosure, the least one suspension arm has a linear configuration.

0064In another aspect of the disclosure, the at least one suspension arm has a curvilinear configuration.

0065In another aspect of the disclosure, the apparatus further comprises a drive wheel independent of the suspension mounting assembly.

0066In another aspect of the disclosure, the drive wheel is positioned to form the upper apex of the continuous track.

0067In another aspect of the disclosure, the apparatus further comprises at least one drive assembly including a motor and a drive shaft, the drive shaft coupled on its first end portion to the motor and coupled on its second end portion to the drive wheel.

0068In another aspect of the disclosure, the apparatus further comprises a dynamic track tensioner configured to provide adjustable tension on the continuous track.

0069In another aspect of the disclosure, the at least a track unit includes a first track unit and a second track unit, the first and second track units coupled to opposing ends of a stabilization bar.

0070In another aspect of the disclosure, the first track unit includes a first drive assembly including a first motor and a first drive shaft, and the second track unit includes a second drive assembly including a second motor and a second drive shaft.

0071In another aspect of the disclosure, the track unit has a triangular configuration.

0072The above Detailed Description includes references to the accompanying drawings, which form a part of the Detailed Description. The Detailed Description should be read with reference to the drawings. The drawings show, by way of illustration, specific embodiments in which the present apparatuses and assemblies can be practiced. These embodiments are also referred to herein as “examples.”

0073The above Detailed Description is intended to be illustrative and not restrictive. For example, the above-described examples (or one or more features or components thereof) can be used in combination with each other. Other embodiments can be used, such as by one of ordinary skill in the art upon reviewing the above Detailed Description. Also, various features or components have been or can be grouped together to streamline the disclosure. This should not be interpreted as intending that an unclaimed disclosed feature is essential to any claim. Rather, inventive subject matter can lie in less than all features of a particular disclosed embodiment.

0074For the following defined terms, certain definitions shall be applied unless a different definition is given elsewhere in this patent document. The terms “a,” “an,” and “the” are used to include one or more than one, independent of any other instances or usages of “at least one” or “one or more.” The term “or” is used to refer to a nonexclusive or, such that “A or B” includes “A but not B,” “B but not A,” and “A and B.”

0075The scope of the present multi-terrain transport apparatuses and included assemblies should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. In the appended claims, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Also, in the following claims, the terms “including” and “comprising” are open-ended; that is, an assembly that includes features or components in addition to those listed after such a term in a claim are still deemed to fall within the scope of that claim. Moreover, in the following claims, the terms “first,” “second” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements on their objects.